1 /*-
2 * Copyright (c) 1982, 1986 The Regents of the University of California.
3 * Copyright (c) 1989, 1990 William Jolitz
4 * Copyright (c) 1994 John Dyson
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * the Systems Programming Group of the University of Utah Computer
9 * Science Department, and William Jolitz.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. All advertising materials mentioning features or use of this software
20 * must display the following acknowledgement:
21 * This product includes software developed by the University of
22 * California, Berkeley and its contributors.
23 * 4. Neither the name of the University nor the names of its contributors
24 * may be used to endorse or promote products derived from this software
25 * without specific prior written permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37 * SUCH DAMAGE.
38 *
39 * from: @(#)vm_machdep.c 7.3 (Berkeley) 5/13/91
40 * Utah $Hdr: vm_machdep.c 1.16.1.1 89/06/23$
41 */
42
43 #include <sys/cdefs.h>
44 __FBSDID("$FreeBSD: releng/10.0/sys/i386/i386/vm_machdep.c 255827 2013-09-23 20:14:15Z kib $");
45
46 #include "opt_isa.h"
47 #include "opt_npx.h"
48 #include "opt_reset.h"
49 #include "opt_cpu.h"
50 #include "opt_xbox.h"
51
52 #include <sys/param.h>
53 #include <sys/systm.h>
54 #include <sys/bio.h>
55 #include <sys/buf.h>
56 #include <sys/kernel.h>
57 #include <sys/ktr.h>
58 #include <sys/lock.h>
59 #include <sys/malloc.h>
60 #include <sys/mbuf.h>
61 #include <sys/mutex.h>
62 #include <sys/pioctl.h>
63 #include <sys/proc.h>
64 #include <sys/sysent.h>
65 #include <sys/sf_buf.h>
66 #include <sys/smp.h>
67 #include <sys/sched.h>
68 #include <sys/sysctl.h>
69 #include <sys/unistd.h>
70 #include <sys/vnode.h>
71 #include <sys/vmmeter.h>
72
73 #include <machine/cpu.h>
74 #include <machine/cputypes.h>
75 #include <machine/md_var.h>
76 #include <machine/pcb.h>
77 #include <machine/pcb_ext.h>
78 #include <machine/smp.h>
79 #include <machine/vm86.h>
80
81 #ifdef CPU_ELAN
82 #include <machine/elan_mmcr.h>
83 #endif
84
85 #include <vm/vm.h>
86 #include <vm/vm_extern.h>
87 #include <vm/vm_kern.h>
88 #include <vm/vm_page.h>
89 #include <vm/vm_map.h>
90 #include <vm/vm_param.h>
91
92 #ifdef XEN
93 #include <xen/hypervisor.h>
94 #endif
95 #ifdef PC98
96 #include <pc98/cbus/cbus.h>
97 #else
98 #include <x86/isa/isa.h>
99 #endif
100
101 #ifdef XBOX
102 #include <machine/xbox.h>
103 #endif
104
105 #ifndef NSFBUFS
106 #define NSFBUFS (512 + maxusers * 16)
107 #endif
108
109 _Static_assert(OFFSETOF_CURTHREAD == offsetof(struct pcpu, pc_curthread),
110 "OFFSETOF_CURTHREAD does not correspond with offset of pc_curthread.");
111 _Static_assert(OFFSETOF_CURPCB == offsetof(struct pcpu, pc_curpcb),
112 "OFFSETOF_CURPCB does not correspond with offset of pc_curpcb.");
113
114 static void cpu_reset_real(void);
115 #ifdef SMP
116 static void cpu_reset_proxy(void);
117 static u_int cpu_reset_proxyid;
118 static volatile u_int cpu_reset_proxy_active;
119 #endif
120
121 static int nsfbufs;
122 static int nsfbufspeak;
123 static int nsfbufsused;
124
125 SYSCTL_INT(_kern_ipc, OID_AUTO, nsfbufs, CTLFLAG_RDTUN, &nsfbufs, 0,
126 "Maximum number of sendfile(2) sf_bufs available");
127 SYSCTL_INT(_kern_ipc, OID_AUTO, nsfbufspeak, CTLFLAG_RD, &nsfbufspeak, 0,
128 "Number of sendfile(2) sf_bufs at peak usage");
129 SYSCTL_INT(_kern_ipc, OID_AUTO, nsfbufsused, CTLFLAG_RD, &nsfbufsused, 0,
130 "Number of sendfile(2) sf_bufs in use");
131
132 static void sf_buf_init(void *arg);
133 SYSINIT(sock_sf, SI_SUB_MBUF, SI_ORDER_ANY, sf_buf_init, NULL);
134
135 LIST_HEAD(sf_head, sf_buf);
136
137 /*
138 * A hash table of active sendfile(2) buffers
139 */
140 static struct sf_head *sf_buf_active;
141 static u_long sf_buf_hashmask;
142
143 #define SF_BUF_HASH(m) (((m) - vm_page_array) & sf_buf_hashmask)
144
145 static TAILQ_HEAD(, sf_buf) sf_buf_freelist;
146 static u_int sf_buf_alloc_want;
147
148 /*
149 * A lock used to synchronize access to the hash table and free list
150 */
151 static struct mtx sf_buf_lock;
152
153 extern int _ucodesel, _udatasel;
154
155 /*
156 * Finish a fork operation, with process p2 nearly set up.
157 * Copy and update the pcb, set up the stack so that the child
158 * ready to run and return to user mode.
159 */
160 void
161 cpu_fork(td1, p2, td2, flags)
162 register struct thread *td1;
163 register struct proc *p2;
164 struct thread *td2;
165 int flags;
166 {
167 register struct proc *p1;
168 struct pcb *pcb2;
169 struct mdproc *mdp2;
170
171 p1 = td1->td_proc;
172 if ((flags & RFPROC) == 0) {
173 if ((flags & RFMEM) == 0) {
174 /* unshare user LDT */
175 struct mdproc *mdp1 = &p1->p_md;
176 struct proc_ldt *pldt, *pldt1;
177
178 mtx_lock_spin(&dt_lock);
179 if ((pldt1 = mdp1->md_ldt) != NULL &&
180 pldt1->ldt_refcnt > 1) {
181 pldt = user_ldt_alloc(mdp1, pldt1->ldt_len);
182 if (pldt == NULL)
183 panic("could not copy LDT");
184 mdp1->md_ldt = pldt;
185 set_user_ldt(mdp1);
186 user_ldt_deref(pldt1);
187 } else
188 mtx_unlock_spin(&dt_lock);
189 }
190 return;
191 }
192
193 /* Ensure that td1's pcb is up to date. */
194 if (td1 == curthread)
195 td1->td_pcb->pcb_gs = rgs();
196 #ifdef DEV_NPX
197 critical_enter();
198 if (PCPU_GET(fpcurthread) == td1)
199 npxsave(td1->td_pcb->pcb_save);
200 critical_exit();
201 #endif
202
203 /* Point the pcb to the top of the stack */
204 pcb2 = (struct pcb *)(td2->td_kstack +
205 td2->td_kstack_pages * PAGE_SIZE) - 1;
206 td2->td_pcb = pcb2;
207
208 /* Copy td1's pcb */
209 bcopy(td1->td_pcb, pcb2, sizeof(*pcb2));
210
211 /* Properly initialize pcb_save */
212 pcb2->pcb_save = &pcb2->pcb_user_save;
213
214 /* Point mdproc and then copy over td1's contents */
215 mdp2 = &p2->p_md;
216 bcopy(&p1->p_md, mdp2, sizeof(*mdp2));
217
218 /*
219 * Create a new fresh stack for the new process.
220 * Copy the trap frame for the return to user mode as if from a
221 * syscall. This copies most of the user mode register values.
222 * The -16 is so we can expand the trapframe if we go to vm86.
223 */
224 td2->td_frame = (struct trapframe *)((caddr_t)td2->td_pcb - 16) - 1;
225 bcopy(td1->td_frame, td2->td_frame, sizeof(struct trapframe));
226
227 td2->td_frame->tf_eax = 0; /* Child returns zero */
228 td2->td_frame->tf_eflags &= ~PSL_C; /* success */
229 td2->td_frame->tf_edx = 1;
230
231 /*
232 * If the parent process has the trap bit set (i.e. a debugger had
233 * single stepped the process to the system call), we need to clear
234 * the trap flag from the new frame unless the debugger had set PF_FORK
235 * on the parent. Otherwise, the child will receive a (likely
236 * unexpected) SIGTRAP when it executes the first instruction after
237 * returning to userland.
238 */
239 if ((p1->p_pfsflags & PF_FORK) == 0)
240 td2->td_frame->tf_eflags &= ~PSL_T;
241
242 /*
243 * Set registers for trampoline to user mode. Leave space for the
244 * return address on stack. These are the kernel mode register values.
245 */
246 #ifdef PAE
247 pcb2->pcb_cr3 = vtophys(vmspace_pmap(p2->p_vmspace)->pm_pdpt);
248 #else
249 pcb2->pcb_cr3 = vtophys(vmspace_pmap(p2->p_vmspace)->pm_pdir);
250 #endif
251 pcb2->pcb_edi = 0;
252 pcb2->pcb_esi = (int)fork_return; /* fork_trampoline argument */
253 pcb2->pcb_ebp = 0;
254 pcb2->pcb_esp = (int)td2->td_frame - sizeof(void *);
255 pcb2->pcb_ebx = (int)td2; /* fork_trampoline argument */
256 pcb2->pcb_eip = (int)fork_trampoline;
257 pcb2->pcb_psl = PSL_KERNEL; /* ints disabled */
258 /*-
259 * pcb2->pcb_dr*: cloned above.
260 * pcb2->pcb_savefpu: cloned above.
261 * pcb2->pcb_flags: cloned above.
262 * pcb2->pcb_onfault: cloned above (always NULL here?).
263 * pcb2->pcb_gs: cloned above.
264 * pcb2->pcb_ext: cleared below.
265 */
266
267 /*
268 * XXX don't copy the i/o pages. this should probably be fixed.
269 */
270 pcb2->pcb_ext = 0;
271
272 /* Copy the LDT, if necessary. */
273 mtx_lock_spin(&dt_lock);
274 if (mdp2->md_ldt != NULL) {
275 if (flags & RFMEM) {
276 mdp2->md_ldt->ldt_refcnt++;
277 } else {
278 mdp2->md_ldt = user_ldt_alloc(mdp2,
279 mdp2->md_ldt->ldt_len);
280 if (mdp2->md_ldt == NULL)
281 panic("could not copy LDT");
282 }
283 }
284 mtx_unlock_spin(&dt_lock);
285
286 /* Setup to release spin count in fork_exit(). */
287 td2->td_md.md_spinlock_count = 1;
288 /*
289 * XXX XEN need to check on PSL_USER is handled
290 */
291 td2->td_md.md_saved_flags = PSL_KERNEL | PSL_I;
292 /*
293 * Now, cpu_switch() can schedule the new process.
294 * pcb_esp is loaded pointing to the cpu_switch() stack frame
295 * containing the return address when exiting cpu_switch.
296 * This will normally be to fork_trampoline(), which will have
297 * %ebx loaded with the new proc's pointer. fork_trampoline()
298 * will set up a stack to call fork_return(p, frame); to complete
299 * the return to user-mode.
300 */
301 }
302
303 /*
304 * Intercept the return address from a freshly forked process that has NOT
305 * been scheduled yet.
306 *
307 * This is needed to make kernel threads stay in kernel mode.
308 */
309 void
310 cpu_set_fork_handler(td, func, arg)
311 struct thread *td;
312 void (*func)(void *);
313 void *arg;
314 {
315 /*
316 * Note that the trap frame follows the args, so the function
317 * is really called like this: func(arg, frame);
318 */
319 td->td_pcb->pcb_esi = (int) func; /* function */
320 td->td_pcb->pcb_ebx = (int) arg; /* first arg */
321 }
322
323 void
324 cpu_exit(struct thread *td)
325 {
326
327 /*
328 * If this process has a custom LDT, release it. Reset pc->pcb_gs
329 * and %gs before we free it in case they refer to an LDT entry.
330 */
331 mtx_lock_spin(&dt_lock);
332 if (td->td_proc->p_md.md_ldt) {
333 td->td_pcb->pcb_gs = _udatasel;
334 load_gs(_udatasel);
335 user_ldt_free(td);
336 } else
337 mtx_unlock_spin(&dt_lock);
338 }
339
340 void
341 cpu_thread_exit(struct thread *td)
342 {
343
344 #ifdef DEV_NPX
345 critical_enter();
346 if (td == PCPU_GET(fpcurthread))
347 npxdrop();
348 critical_exit();
349 #endif
350
351 /* Disable any hardware breakpoints. */
352 if (td->td_pcb->pcb_flags & PCB_DBREGS) {
353 reset_dbregs();
354 td->td_pcb->pcb_flags &= ~PCB_DBREGS;
355 }
356 }
357
358 void
359 cpu_thread_clean(struct thread *td)
360 {
361 struct pcb *pcb;
362
363 pcb = td->td_pcb;
364 if (pcb->pcb_ext != NULL) {
365 /* if (pcb->pcb_ext->ext_refcount-- == 1) ?? */
366 /*
367 * XXX do we need to move the TSS off the allocated pages
368 * before freeing them? (not done here)
369 */
370 kmem_free(kernel_arena, (vm_offset_t)pcb->pcb_ext,
371 ctob(IOPAGES + 1));
372 pcb->pcb_ext = NULL;
373 }
374 }
375
376 void
377 cpu_thread_swapin(struct thread *td)
378 {
379 }
380
381 void
382 cpu_thread_swapout(struct thread *td)
383 {
384 }
385
386 void
387 cpu_thread_alloc(struct thread *td)
388 {
389
390 td->td_pcb = (struct pcb *)(td->td_kstack +
391 td->td_kstack_pages * PAGE_SIZE) - 1;
392 td->td_frame = (struct trapframe *)((caddr_t)td->td_pcb - 16) - 1;
393 td->td_pcb->pcb_ext = NULL;
394 td->td_pcb->pcb_save = &td->td_pcb->pcb_user_save;
395 }
396
397 void
398 cpu_thread_free(struct thread *td)
399 {
400
401 cpu_thread_clean(td);
402 }
403
404 void
405 cpu_set_syscall_retval(struct thread *td, int error)
406 {
407
408 switch (error) {
409 case 0:
410 td->td_frame->tf_eax = td->td_retval[0];
411 td->td_frame->tf_edx = td->td_retval[1];
412 td->td_frame->tf_eflags &= ~PSL_C;
413 break;
414
415 case ERESTART:
416 /*
417 * Reconstruct pc, assuming lcall $X,y is 7 bytes, int
418 * 0x80 is 2 bytes. We saved this in tf_err.
419 */
420 td->td_frame->tf_eip -= td->td_frame->tf_err;
421 break;
422
423 case EJUSTRETURN:
424 break;
425
426 default:
427 if (td->td_proc->p_sysent->sv_errsize) {
428 if (error >= td->td_proc->p_sysent->sv_errsize)
429 error = -1; /* XXX */
430 else
431 error = td->td_proc->p_sysent->sv_errtbl[error];
432 }
433 td->td_frame->tf_eax = error;
434 td->td_frame->tf_eflags |= PSL_C;
435 break;
436 }
437 }
438
439 /*
440 * Initialize machine state (pcb and trap frame) for a new thread about to
441 * upcall. Put enough state in the new thread's PCB to get it to go back
442 * userret(), where we can intercept it again to set the return (upcall)
443 * Address and stack, along with those from upcals that are from other sources
444 * such as those generated in thread_userret() itself.
445 */
446 void
447 cpu_set_upcall(struct thread *td, struct thread *td0)
448 {
449 struct pcb *pcb2;
450
451 /* Point the pcb to the top of the stack. */
452 pcb2 = td->td_pcb;
453
454 /*
455 * Copy the upcall pcb. This loads kernel regs.
456 * Those not loaded individually below get their default
457 * values here.
458 */
459 bcopy(td0->td_pcb, pcb2, sizeof(*pcb2));
460 pcb2->pcb_flags &= ~(PCB_NPXINITDONE | PCB_NPXUSERINITDONE);
461 pcb2->pcb_save = &pcb2->pcb_user_save;
462
463 /*
464 * Create a new fresh stack for the new thread.
465 */
466 bcopy(td0->td_frame, td->td_frame, sizeof(struct trapframe));
467
468 /* If the current thread has the trap bit set (i.e. a debugger had
469 * single stepped the process to the system call), we need to clear
470 * the trap flag from the new frame. Otherwise, the new thread will
471 * receive a (likely unexpected) SIGTRAP when it executes the first
472 * instruction after returning to userland.
473 */
474 td->td_frame->tf_eflags &= ~PSL_T;
475
476 /*
477 * Set registers for trampoline to user mode. Leave space for the
478 * return address on stack. These are the kernel mode register values.
479 */
480 pcb2->pcb_edi = 0;
481 pcb2->pcb_esi = (int)fork_return; /* trampoline arg */
482 pcb2->pcb_ebp = 0;
483 pcb2->pcb_esp = (int)td->td_frame - sizeof(void *); /* trampoline arg */
484 pcb2->pcb_ebx = (int)td; /* trampoline arg */
485 pcb2->pcb_eip = (int)fork_trampoline;
486 pcb2->pcb_psl &= ~(PSL_I); /* interrupts must be disabled */
487 pcb2->pcb_gs = rgs();
488 /*
489 * If we didn't copy the pcb, we'd need to do the following registers:
490 * pcb2->pcb_cr3: cloned above.
491 * pcb2->pcb_dr*: cloned above.
492 * pcb2->pcb_savefpu: cloned above.
493 * pcb2->pcb_flags: cloned above.
494 * pcb2->pcb_onfault: cloned above (always NULL here?).
495 * pcb2->pcb_gs: cloned above.
496 * pcb2->pcb_ext: cleared below.
497 */
498 pcb2->pcb_ext = NULL;
499
500 /* Setup to release spin count in fork_exit(). */
501 td->td_md.md_spinlock_count = 1;
502 td->td_md.md_saved_flags = PSL_KERNEL | PSL_I;
503 }
504
505 /*
506 * Set that machine state for performing an upcall that has to
507 * be done in thread_userret() so that those upcalls generated
508 * in thread_userret() itself can be done as well.
509 */
510 void
511 cpu_set_upcall_kse(struct thread *td, void (*entry)(void *), void *arg,
512 stack_t *stack)
513 {
514
515 /*
516 * Do any extra cleaning that needs to be done.
517 * The thread may have optional components
518 * that are not present in a fresh thread.
519 * This may be a recycled thread so make it look
520 * as though it's newly allocated.
521 */
522 cpu_thread_clean(td);
523
524 /*
525 * Set the trap frame to point at the beginning of the uts
526 * function.
527 */
528 td->td_frame->tf_ebp = 0;
529 td->td_frame->tf_esp =
530 (((int)stack->ss_sp + stack->ss_size - 4) & ~0x0f) - 4;
531 td->td_frame->tf_eip = (int)entry;
532
533 /*
534 * Pass the address of the mailbox for this kse to the uts
535 * function as a parameter on the stack.
536 */
537 suword((void *)(td->td_frame->tf_esp + sizeof(void *)),
538 (int)arg);
539 }
540
541 int
542 cpu_set_user_tls(struct thread *td, void *tls_base)
543 {
544 struct segment_descriptor sd;
545 uint32_t base;
546
547 /*
548 * Construct a descriptor and store it in the pcb for
549 * the next context switch. Also store it in the gdt
550 * so that the load of tf_fs into %fs will activate it
551 * at return to userland.
552 */
553 base = (uint32_t)tls_base;
554 sd.sd_lobase = base & 0xffffff;
555 sd.sd_hibase = (base >> 24) & 0xff;
556 sd.sd_lolimit = 0xffff; /* 4GB limit, wraps around */
557 sd.sd_hilimit = 0xf;
558 sd.sd_type = SDT_MEMRWA;
559 sd.sd_dpl = SEL_UPL;
560 sd.sd_p = 1;
561 sd.sd_xx = 0;
562 sd.sd_def32 = 1;
563 sd.sd_gran = 1;
564 critical_enter();
565 /* set %gs */
566 td->td_pcb->pcb_gsd = sd;
567 if (td == curthread) {
568 PCPU_GET(fsgs_gdt)[1] = sd;
569 load_gs(GSEL(GUGS_SEL, SEL_UPL));
570 }
571 critical_exit();
572 return (0);
573 }
574
575 /*
576 * Convert kernel VA to physical address
577 */
578 vm_paddr_t
579 kvtop(void *addr)
580 {
581 vm_paddr_t pa;
582
583 pa = pmap_kextract((vm_offset_t)addr);
584 if (pa == 0)
585 panic("kvtop: zero page frame");
586 return (pa);
587 }
588
589 #ifdef SMP
590 static void
591 cpu_reset_proxy()
592 {
593 cpuset_t tcrp;
594
595 cpu_reset_proxy_active = 1;
596 while (cpu_reset_proxy_active == 1)
597 ; /* Wait for other cpu to see that we've started */
598 CPU_SETOF(cpu_reset_proxyid, &tcrp);
599 stop_cpus(tcrp);
600 printf("cpu_reset_proxy: Stopped CPU %d\n", cpu_reset_proxyid);
601 DELAY(1000000);
602 cpu_reset_real();
603 }
604 #endif
605
606 void
607 cpu_reset()
608 {
609 #ifdef XBOX
610 if (arch_i386_is_xbox) {
611 /* Kick the PIC16L, it can reboot the box */
612 pic16l_reboot();
613 for (;;);
614 }
615 #endif
616
617 #ifdef SMP
618 cpuset_t map;
619 u_int cnt;
620
621 if (smp_active) {
622 map = all_cpus;
623 CPU_CLR(PCPU_GET(cpuid), &map);
624 CPU_NAND(&map, &stopped_cpus);
625 if (!CPU_EMPTY(&map)) {
626 printf("cpu_reset: Stopping other CPUs\n");
627 stop_cpus(map);
628 }
629
630 if (PCPU_GET(cpuid) != 0) {
631 cpu_reset_proxyid = PCPU_GET(cpuid);
632 cpustop_restartfunc = cpu_reset_proxy;
633 cpu_reset_proxy_active = 0;
634 printf("cpu_reset: Restarting BSP\n");
635
636 /* Restart CPU #0. */
637 /* XXX: restart_cpus(1 << 0); */
638 CPU_SETOF(0, &started_cpus);
639 wmb();
640
641 cnt = 0;
642 while (cpu_reset_proxy_active == 0 && cnt < 10000000)
643 cnt++; /* Wait for BSP to announce restart */
644 if (cpu_reset_proxy_active == 0)
645 printf("cpu_reset: Failed to restart BSP\n");
646 enable_intr();
647 cpu_reset_proxy_active = 2;
648
649 while (1);
650 /* NOTREACHED */
651 }
652
653 DELAY(1000000);
654 }
655 #endif
656 cpu_reset_real();
657 /* NOTREACHED */
658 }
659
660 static void
661 cpu_reset_real()
662 {
663 struct region_descriptor null_idt;
664 #ifndef PC98
665 int b;
666 #endif
667
668 disable_intr();
669 #ifdef XEN
670 if (smp_processor_id() == 0)
671 HYPERVISOR_shutdown(SHUTDOWN_reboot);
672 else
673 HYPERVISOR_shutdown(SHUTDOWN_poweroff);
674 #endif
675 #ifdef CPU_ELAN
676 if (elan_mmcr != NULL)
677 elan_mmcr->RESCFG = 1;
678 #endif
679
680 if (cpu == CPU_GEODE1100) {
681 /* Attempt Geode's own reset */
682 outl(0xcf8, 0x80009044ul);
683 outl(0xcfc, 0xf);
684 }
685
686 #ifdef PC98
687 /*
688 * Attempt to do a CPU reset via CPU reset port.
689 */
690 if ((inb(0x35) & 0xa0) != 0xa0) {
691 outb(0x37, 0x0f); /* SHUT0 = 0. */
692 outb(0x37, 0x0b); /* SHUT1 = 0. */
693 }
694 outb(0xf0, 0x00); /* Reset. */
695 #else
696 #if !defined(BROKEN_KEYBOARD_RESET)
697 /*
698 * Attempt to do a CPU reset via the keyboard controller,
699 * do not turn off GateA20, as any machine that fails
700 * to do the reset here would then end up in no man's land.
701 */
702 outb(IO_KBD + 4, 0xFE);
703 DELAY(500000); /* wait 0.5 sec to see if that did it */
704 #endif
705
706 /*
707 * Attempt to force a reset via the Reset Control register at
708 * I/O port 0xcf9. Bit 2 forces a system reset when it
709 * transitions from 0 to 1. Bit 1 selects the type of reset
710 * to attempt: 0 selects a "soft" reset, and 1 selects a
711 * "hard" reset. We try a "hard" reset. The first write sets
712 * bit 1 to select a "hard" reset and clears bit 2. The
713 * second write forces a 0 -> 1 transition in bit 2 to trigger
714 * a reset.
715 */
716 outb(0xcf9, 0x2);
717 outb(0xcf9, 0x6);
718 DELAY(500000); /* wait 0.5 sec to see if that did it */
719
720 /*
721 * Attempt to force a reset via the Fast A20 and Init register
722 * at I/O port 0x92. Bit 1 serves as an alternate A20 gate.
723 * Bit 0 asserts INIT# when set to 1. We are careful to only
724 * preserve bit 1 while setting bit 0. We also must clear bit
725 * 0 before setting it if it isn't already clear.
726 */
727 b = inb(0x92);
728 if (b != 0xff) {
729 if ((b & 0x1) != 0)
730 outb(0x92, b & 0xfe);
731 outb(0x92, b | 0x1);
732 DELAY(500000); /* wait 0.5 sec to see if that did it */
733 }
734 #endif /* PC98 */
735
736 printf("No known reset method worked, attempting CPU shutdown\n");
737 DELAY(1000000); /* wait 1 sec for printf to complete */
738
739 /* Wipe the IDT. */
740 null_idt.rd_limit = 0;
741 null_idt.rd_base = 0;
742 lidt(&null_idt);
743
744 /* "good night, sweet prince .... <THUNK!>" */
745 breakpoint();
746
747 /* NOTREACHED */
748 while(1);
749 }
750
751 /*
752 * Allocate a pool of sf_bufs (sendfile(2) or "super-fast" if you prefer. :-))
753 */
754 static void
755 sf_buf_init(void *arg)
756 {
757 struct sf_buf *sf_bufs;
758 vm_offset_t sf_base;
759 int i;
760
761 nsfbufs = NSFBUFS;
762 TUNABLE_INT_FETCH("kern.ipc.nsfbufs", &nsfbufs);
763
764 sf_buf_active = hashinit(nsfbufs, M_TEMP, &sf_buf_hashmask);
765 TAILQ_INIT(&sf_buf_freelist);
766 sf_base = kva_alloc(nsfbufs * PAGE_SIZE);
767 sf_bufs = malloc(nsfbufs * sizeof(struct sf_buf), M_TEMP,
768 M_NOWAIT | M_ZERO);
769 for (i = 0; i < nsfbufs; i++) {
770 sf_bufs[i].kva = sf_base + i * PAGE_SIZE;
771 TAILQ_INSERT_TAIL(&sf_buf_freelist, &sf_bufs[i], free_entry);
772 }
773 sf_buf_alloc_want = 0;
774 mtx_init(&sf_buf_lock, "sf_buf", NULL, MTX_DEF);
775 }
776
777 /*
778 * Invalidate the cache lines that may belong to the page, if
779 * (possibly old) mapping of the page by sf buffer exists. Returns
780 * TRUE when mapping was found and cache invalidated.
781 */
782 boolean_t
783 sf_buf_invalidate_cache(vm_page_t m)
784 {
785 struct sf_head *hash_list;
786 struct sf_buf *sf;
787 boolean_t ret;
788
789 hash_list = &sf_buf_active[SF_BUF_HASH(m)];
790 ret = FALSE;
791 mtx_lock(&sf_buf_lock);
792 LIST_FOREACH(sf, hash_list, list_entry) {
793 if (sf->m == m) {
794 /*
795 * Use pmap_qenter to update the pte for
796 * existing mapping, in particular, the PAT
797 * settings are recalculated.
798 */
799 pmap_qenter(sf->kva, &m, 1);
800 pmap_invalidate_cache_range(sf->kva, sf->kva +
801 PAGE_SIZE);
802 ret = TRUE;
803 break;
804 }
805 }
806 mtx_unlock(&sf_buf_lock);
807 return (ret);
808 }
809
810 /*
811 * Get an sf_buf from the freelist. May block if none are available.
812 */
813 struct sf_buf *
814 sf_buf_alloc(struct vm_page *m, int flags)
815 {
816 pt_entry_t opte, *ptep;
817 struct sf_head *hash_list;
818 struct sf_buf *sf;
819 #ifdef SMP
820 cpuset_t other_cpus;
821 u_int cpuid;
822 #endif
823 int error;
824
825 KASSERT(curthread->td_pinned > 0 || (flags & SFB_CPUPRIVATE) == 0,
826 ("sf_buf_alloc(SFB_CPUPRIVATE): curthread not pinned"));
827 hash_list = &sf_buf_active[SF_BUF_HASH(m)];
828 mtx_lock(&sf_buf_lock);
829 LIST_FOREACH(sf, hash_list, list_entry) {
830 if (sf->m == m) {
831 sf->ref_count++;
832 if (sf->ref_count == 1) {
833 TAILQ_REMOVE(&sf_buf_freelist, sf, free_entry);
834 nsfbufsused++;
835 nsfbufspeak = imax(nsfbufspeak, nsfbufsused);
836 }
837 #ifdef SMP
838 goto shootdown;
839 #else
840 goto done;
841 #endif
842 }
843 }
844 while ((sf = TAILQ_FIRST(&sf_buf_freelist)) == NULL) {
845 if (flags & SFB_NOWAIT)
846 goto done;
847 sf_buf_alloc_want++;
848 SFSTAT_INC(sf_allocwait);
849 error = msleep(&sf_buf_freelist, &sf_buf_lock,
850 (flags & SFB_CATCH) ? PCATCH | PVM : PVM, "sfbufa", 0);
851 sf_buf_alloc_want--;
852
853 /*
854 * If we got a signal, don't risk going back to sleep.
855 */
856 if (error)
857 goto done;
858 }
859 TAILQ_REMOVE(&sf_buf_freelist, sf, free_entry);
860 if (sf->m != NULL)
861 LIST_REMOVE(sf, list_entry);
862 LIST_INSERT_HEAD(hash_list, sf, list_entry);
863 sf->ref_count = 1;
864 sf->m = m;
865 nsfbufsused++;
866 nsfbufspeak = imax(nsfbufspeak, nsfbufsused);
867
868 /*
869 * Update the sf_buf's virtual-to-physical mapping, flushing the
870 * virtual address from the TLB. Since the reference count for
871 * the sf_buf's old mapping was zero, that mapping is not
872 * currently in use. Consequently, there is no need to exchange
873 * the old and new PTEs atomically, even under PAE.
874 */
875 ptep = vtopte(sf->kva);
876 opte = *ptep;
877 #ifdef XEN
878 PT_SET_MA(sf->kva, xpmap_ptom(VM_PAGE_TO_PHYS(m)) | pgeflag
879 | PG_RW | PG_V | pmap_cache_bits(m->md.pat_mode, 0));
880 #else
881 *ptep = VM_PAGE_TO_PHYS(m) | pgeflag | PG_RW | PG_V |
882 pmap_cache_bits(m->md.pat_mode, 0);
883 #endif
884
885 /*
886 * Avoid unnecessary TLB invalidations: If the sf_buf's old
887 * virtual-to-physical mapping was not used, then any processor
888 * that has invalidated the sf_buf's virtual address from its TLB
889 * since the last used mapping need not invalidate again.
890 */
891 #ifdef SMP
892 if ((opte & (PG_V | PG_A)) == (PG_V | PG_A))
893 CPU_ZERO(&sf->cpumask);
894 shootdown:
895 sched_pin();
896 cpuid = PCPU_GET(cpuid);
897 if (!CPU_ISSET(cpuid, &sf->cpumask)) {
898 CPU_SET(cpuid, &sf->cpumask);
899 invlpg(sf->kva);
900 }
901 if ((flags & SFB_CPUPRIVATE) == 0) {
902 other_cpus = all_cpus;
903 CPU_CLR(cpuid, &other_cpus);
904 CPU_NAND(&other_cpus, &sf->cpumask);
905 if (!CPU_EMPTY(&other_cpus)) {
906 CPU_OR(&sf->cpumask, &other_cpus);
907 smp_masked_invlpg(other_cpus, sf->kva);
908 }
909 }
910 sched_unpin();
911 #else
912 if ((opte & (PG_V | PG_A)) == (PG_V | PG_A))
913 pmap_invalidate_page(kernel_pmap, sf->kva);
914 #endif
915 done:
916 mtx_unlock(&sf_buf_lock);
917 return (sf);
918 }
919
920 /*
921 * Remove a reference from the given sf_buf, adding it to the free
922 * list when its reference count reaches zero. A freed sf_buf still,
923 * however, retains its virtual-to-physical mapping until it is
924 * recycled or reactivated by sf_buf_alloc(9).
925 */
926 void
927 sf_buf_free(struct sf_buf *sf)
928 {
929
930 mtx_lock(&sf_buf_lock);
931 sf->ref_count--;
932 if (sf->ref_count == 0) {
933 TAILQ_INSERT_TAIL(&sf_buf_freelist, sf, free_entry);
934 nsfbufsused--;
935 #ifdef XEN
936 /*
937 * Xen doesn't like having dangling R/W mappings
938 */
939 pmap_qremove(sf->kva, 1);
940 sf->m = NULL;
941 LIST_REMOVE(sf, list_entry);
942 #endif
943 if (sf_buf_alloc_want > 0)
944 wakeup(&sf_buf_freelist);
945 }
946 mtx_unlock(&sf_buf_lock);
947 }
948
949 /*
950 * Software interrupt handler for queued VM system processing.
951 */
952 void
953 swi_vm(void *dummy)
954 {
955 if (busdma_swi_pending != 0)
956 busdma_swi();
957 }
958
959 /*
960 * Tell whether this address is in some physical memory region.
961 * Currently used by the kernel coredump code in order to avoid
962 * dumping the ``ISA memory hole'' which could cause indefinite hangs,
963 * or other unpredictable behaviour.
964 */
965
966 int
967 is_physical_memory(vm_paddr_t addr)
968 {
969
970 #ifdef DEV_ISA
971 /* The ISA ``memory hole''. */
972 if (addr >= 0xa0000 && addr < 0x100000)
973 return 0;
974 #endif
975
976 /*
977 * stuff other tests for known memory-mapped devices (PCI?)
978 * here
979 */
980
981 return 1;
982 }
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